Articles

Pick, Place and Show

Consider Norlen Inc. The contract stamper, fabricator and assembler, established in 1964 and calling Schofield, WI, home, grew at a 26 percent clip in 2007 and is expected to maintain double-digit growth in 2008 and 2009. The supplier to nearly every major market except automotive achieves such performance by focusing on its core competencies: operational excellence, innovative solutions and human capital. Superiority in diverse production processes combined with well-trained, well-motivated personnel—120 employees across multiple shifts in 180,000 sq. ft. of manufacturing space—undeniably go a long in attaining these results, but innovative solutions, namely the deployment of technology and the use of automation to drive costs out of the business model, push the company over the top.

Strives to be Technology Leader

“We have achieved a cost structure that is very competitive in a global market,” explains Jeff Brillhart, vice president and general manger at Norlen. “Customers want to align themselves with suppliers that are not status quo: ‘Look what we do, we do what everybody else does.’ We lead in technology in the contract sector—there are very few shops as automated as Norlen. At the end of the day, our customers and our future customers want a competitive price for high-quality parts delivered on time every time.”

Automation, claims Brillhart, is what enables Norlen to meet these customer demands.

For example, the company employs robots, as part of an automation drive that began about three years ago, for part polishing, arc and resistance welding, assembly and material handling. Since 2005, Norlen’s sales have tripled while labor costs have dropped by 37 percent.

Demand Calls for Two-Press Cell with Robotic Tending

Part of that focus on automation is formation of a robotic press-tending cell, where a 150-kg six-axis robot from KUKA Robotics Corp. USA, Clinton Township, MI, loads and unloads two presses—a 200-ton straightside and a 275-ton gap-frame model, both formerly hand-fed.

“Demand is so great that we need this additional capacity,” says Brillhart, explaining the use of two presses in the cell.

The presses are part of Norlen’s eight-press stable—five of those coil-fed—in capacities from 100 to 500 tons. The presses typically work with carbon steel in thicknesses from 18 gauge to 0.25 in., and also process 200-, 300- and 400-series stainless steels as well as some nonferrous alloys. About half of the stampings produced at Norlen ship directly to customers right off of the press lines while the rest route to inhouse value-added operations.

“We perform a fair amount of hand-transfer-tooling jobs, so we examined labor content and found that a vast majority of that was tied directly to these highly manual operations,” says Brillhart. “By deploying robots to tend the presses, we achieve a much more favorable cost model.”

In operation, stacks of material—either blanks or parts from a coil-fed press operation that require secondary forming—enter the cell and the robot picks material from the stack and loads and unloads the presses.“Sometimes the robot will palletize or stack parts after forming, or parts travel on a conveyor and dump into a crate destined for a downstream operation,” explains Brillhart. “A form and ship job sends parts from conveyor to crate and then to shipping, or they may be weldments stacked after forming and moved to our weld cells. In some cases the robot may assist with compound-forming operations. For instance, we buy blanks cut to size for an enclosure, and the robot picks the blanks from the stack and moves them through the two-station compound die followed by repalletizing.”

Norlen also produces its own blanks in coil-fed presses, oriented in the robotic press-tending cell for pickup by the robot.

Quick Job Change a Must

The company employs a variety of end-of-arm tooling (EOAT) on the robot, all of it produced inhouse.

“Suction cups comprise the majority of our EOAT, but for some jobs we may need to grip a part and rotate it, so we also use grip-type tooling,” says Brillhart.Quick-disconnect coupling enables rapid changeout of the EOAT, which, along with other quick-die-change efforts, provides job-change shortcuts. That’s extremely important, according to Brillhart.

“We are a low- to mid-volume production house, so changeover efficiency is a priority,” he says. “We will change part jobs 8 to 10 times in a day in this cell and run from 150 to 750 pieces per setup. So we can quickly change the EOAT, call up the job program and be ready to roll. As a result of our attention to quick job change, our changeovers now take only 18 to 22 min. from last part to first part.

“And because we can rotate the robot 180 deg.,” continues Brillhart, “we can tend one press while performing job setup on the other, which helps eliminate idle time.”

Learning to Master the Workcell

While no one denies the efficiencies robots can bring to a pressroom, metalformers traditionally have feared the knowhow that must be acquired to properly set up a robot and keep it online.“When we installed the robot, our staff performed the entire integration, incorporated safety features within the cell, performed all of the programming, and undertook the design and build of our EOAT, because I wanted them to learn this Kuka platform,” Brillhart says, noting that Norlen was committed to bringing in more robots from this company in the future—two other Kuka robots at Norlen occupy welding and assembly cells. “We sent a number of engineers over to Kuka’s technical center in Appleton, WI, for several weeks of training, and brought on some support from that robot supplier to help us through the initial programs and integration. We now have a confident staff that can service and program the robot, and can integrate new projects into the cell. We are fairly self-sufficient now. But again that required a lot of training up front.”

New Plant, Same Focus on Automation

With business continuing to grow, Brillhart says the company plans next year to open another nearby facility that will complement current Norlen manufacturing processes and add some new ones at the request of customers. And Norlen will continue to focus on automation as a path to success.

“We are like everyone else,” he explains. “The cost of goods sold comprise three things: material, labor and overhead. Material is what it is. We can work to buy material at the most competitive price but at the end of the day we can’t predict that price nor can we really have a lot of influence on material cost. For metalformers like us, those that best control labor and overhead typically win the game.” MF